How Heavy Were Those Gold Plates?

Paramount in the story of the Latter-day Saints is the account given by Joseph Smith of a visitation he received from the angel Moroni on September 21, 1823. He stated that after he retired to bed, his room became filled with light. At his bedside stood an angel who called Smith by name and told him that God had a work for the young boy to do. Smith claimed to have been told how, "there was a book deposited, written upon gold plates, giving an account of the former inhabitants of this continent, and the source from whence they sprang" (Joseph Smith – History 1:34).

Smith claims that he was not allowed to retrieve the buried plates for another four years. In verse 54 of his testimony, he related that the day he was allowed to dig up the record came on September 22, 1827. Mormon historian Leonard Arrington notes that, "Sometime after midnight in the early morning hours of September 22, Joseph and Emma drove to the hill, obtained the plates and hid them in an old birch log about three miles from the Smith home. With neighboring ruffians seeking the plates, thinking they were of great monetary worth, Joseph changed the hiding place several times and managed to keep them from being discovered and stolen" ("Mormonism: From Its New York Beginnings," Dialogue, Vol.13, No.3, p.122). Eventually Joseph Smith would bring the plates home to be translated. His mother, Lucy Mack Smith, remembered the day this way:

"The plates were secreted about three miles from home... Joseph, on coming to them, took them from their secret place, and, wrapping them in his linen frock, placed them under his arm and started for home."

After proceeding a short distance, he thought it would be more safe to leave the road and go through the woods. Traveling some distance after he left the road, he came to a large windfall, and as he was jumping over a log, a man sprang up from behind it, and gave him a heavy blow with a gun. Joseph turned around and knocked him down, then ran at the top of his speed. About half a mile further he was attacked again in the same manner as before; he knocked this man down in like manner as the former, and ran on again; and before he reached home he was assaulted the third time. In striking the last one he dislocated his thumb, which, however, he did not notice until he came within sight of the house, when he threw himself down in the corner of the fence in order to recover his breath. As soon as he was able, he arose and came to the house. lie was still altogether speechless from fright and the fatigue of running" (History of Joseph Smith by His Mother, Lucy Smith, pp.107-108).

Smith stated, "These records were engraven on plates which had the appearance of gold, each plate was six inches wide and eight inches long, and not quite so thick as common tin. They were filled with engravings, in Egyptian characters, and bound together in a volume as the leaves of a book, with three rings running through the whole. The volume was something near six inches in thickness, a part of which was sealed" (History of the Church 4:537)

Paintings of Smith show him receiving the plates with outstretched arms or resting on his knee. Although these are just an artist's perception, these descriptions do cause us to ask, "If they really existed, just how heavy would those plates have been given the size and description by Smith?"

Gold weighs 1,204 pounds per cubic foot, so if we use the dimensions given by Smith we can correctly conclude that the plates were 1/6 of a cubit foot. In other words, if the plates were made of gold, they would have weighed 200 pounds. This becomes problematic since no one believes that it is physically possible to carry such a weight for any considerable distance, much less be able to run away from thieves bent on stealing the plates.

In response to this dilemma, proponents argue that the plates would have been considerably lighter due to "air space" between the uneven, hand-made plates. While this may seem plausible to some, this rebuttal becomes tenuous given the soft nature of gold. Plates of gold stacked in the manner described by Smith would easily flatten out, thus displacing any arbitrary "air space" suggested by LDS apologists.

By assuming the plates had an air gap of 50% (a capricious percentage to be sure), Mormon metallurgist Reed Putnam estimates that if the plates were made of pure gold, they would have probably weighed around 100 pounds. Still, this is not at all a reasonable weight that can be carried by even the strongest of New York farm boys. In perspective, that would be like carrying a bag of Portland cement under one's arm.

The possibility of the plates being too heavy for Smith to carry has not escaped the notice of LDS apologists. To credit their founder with the ability to carry such a weight while running at "the top of his speed" would seem to conclude that Smith had no idea how heavy gold really was, thus making it appear that he fabricated this story.

Still, Putnam insists that "the plates were not so heavy that a man could not carry them." In a September, 1966 article in the Improvement Era magazine, he states, "we are not led to believe that the weight of the plates was a great hinderance" (p.789). However, in drawing such a conclusion Putnam and many modern Mormon apologists reject the notion that the plates were made of pure gold. Putnam surmizes that the plates were probably composed of a copper/gold Central American alloy called tumbaga. Though there is no standard for the copper/gold ratio in tumbaga, Mormon apologists naturally insist on a ratio that allows for the plates to be the lightest, presumably 8K gold and copper. In other words, the plates would have been primarily composed of 66% copper and only 33% gold.

Mormon apologists feel that plates made of a stronger alloy makes more sense since plates of pure gold would be too soft and not practical. However, if that is really so, why does Mosiah 8:9 in the Book of Mormon mentions 24 Jaredite plates that were "filled with engravings, and they are of pure gold"?

This argument also fails to take into account a photograph in earlier editions of the Book of Mormon that showed a "gold tablet found in Persia in 1961, dating to the time of Darius II (Fourth century B.C.), covered with cuneiform engravings." The caption went on to say, "This tablet is about the size of the gold plates of the Book of Mormon." In his book entitled An Approach to the Book of Mormon, Dr. Hugh Nibley also mentioned this parallel as evidence to the fact that Smith had plates of gold. If the plates deposited by Moroni were really an alloy made primarily of copper, why go to such lengths?

By insisting that the plates had an air gap of 50%, Putnam concludes that 8K tumbaga plates could have weighed as little as 53 pounds. In other words, it would be like carrying a sack of redi-mix concrete. Given the details of how Smith retrieved the plates, this lighter weight only comforts those who really want (and need) to believe such a fantastic story.

It appears that the tumbaga theory is not always taken too seriously. For example, the May 15, 1999 issue of the LDS Church News ran an article titled "Hands-on opportunity." Speaking of Joseph Smith, it read, "He had also been instructed by an angel, Moroni, who had met with him each year for four years. On his last visit, he was entrusted with plates of solid gold, which he had been translating by the power of the Spirit."

A common response by faithful Latter-day Saints is that God gave Joseph Smith supernatural strength to carry the plates. If that is really the case, why have Mormon apologists gone to great lengths to reconstruct the story in such a way as to get the weight of the plates down to what they feel is a manageable level? If God really intervened, why reinvent the tale? Why not believe Smith could have supernaturally carried 200 pounds under his arm and be done with it? The fact is, no Mormon apologist or LDS leader argues that God gave Smith supernatural strength to carry the plates.

Keep this in mind the next time you stop at a hardware store. Pick up a bag of cement, tuck it under your arm, and imagine yourself carrying it for a distance of three miles running as fast as you can at least part of the way. For added effect you could jump over a display or two.

Related Quotes

"It may be well to state, that the people of God, in ancient days, according to the accounts of men, kept their sacred records on plates of gold, and those of less consequence on plates of brass, copper, wood, &c. see John's biblical archeology, Josephus, and others. These plates were generally made from the sixteenth to the thirty second part of an inch thick (of metal) and something like six by eight inches square, and fastened at the back with three rings through which a rod was put to carry them, or hang them. The word of the Lord, the history of the doings of the children of God, and their genealogy was engraved in a nice workmanlike manner, upon them, in Hebrew, reformed Egyptian, &c. Such was the condition of the plates, from which came the book of Mormon. As may be seen by an allusion in the book of Ether, all that was on them is not translated; wherefore, as they are sacred, when the book of Mormon was translated from them, they were again hid up to the Lord, to come forth again in his own due time." - The Book of Mormon., Evening and Morning Star, vol. 1 (June 1832-May 1833), Vol. I. December, 1832. No. 7., p.58 - 59